The concentration of ozone molecules is decreasing because they’re being broken down. This is being caused by free radical catalysts, such as nitrous oxide, nitric oxide
More good news related to the environment: scientists and researchers have observed signs that the ozone hole above the Antarctic is actually repairing itself!
Presenting the observations in an article published in the journal Science, researchers say that the ozone layer is on track for recovery in the next few decades, thanks to the dedicated efforts of countries all over the world to combat the global threat of ozone depletion.
However, before we talk about this in too much detail, it’s important to understand a thing or two about the ozone layer.
What is the Ozone layer?
The ozone layer is a protective layer enveloping Earth that shields it against harmful ultraviolet radiation from the Sun. Also referred to as the ozone shield, it’s basically a thin region in the lower part of the stratosphere (a component of the atmosphere) that consists of high concentrations of a molecule called ‘ozone’, which has the chemical formula O3. In fact, it is a less stable allotrope of diatomic oxygen (O2), which is the most essential gas in terms of sustaining life on Earth.
Reaction of diatomic and monoatomic oxygen to form ozone in the atmosphere (Photo Credit : NASA / Wikipedia. org)
In contrast to the average concentration of ozone in the atmosphere (0.3 parts per million, i.e. 0.3 ppm), the ozone layer has a much higher concentration of ozone (10 ppm). However, this concentration of ozone, or the ‘thickness’ of the ozone layer, varies geographically and seasonally.
What’s wrong with the ozone layer?
The problem with the ozone layer is something that you’ve probably heard a lot about… it’s becoming depleted. In other words, the concentration of ozone molecules is decreasing because they’re being broken down.
This is being caused by free radical catalysts, such as nitrous oxide, nitric oxide, atomic chlorine and atomic bromine. The concentrations of chlorine and bromine have increased significantly in the past few decades due to the release of chlorofluorocarbons (CFCs) and bromofluorocarbons – both of which are manmade products.
Some good news about Ozone layer
Researchers have recently found that the Antarctic ozone layer has begun showing signs of healing and is expected to continue doing so in the coming years. This positive change is credited to The Montreal Protocol on Substances that deplete the Ozone layer – an international policy that has been in force since January 1, 1989.
As the name clearly signifies, the policy was designed to reduce the production and consumption of substances (like halons and chlorofluorocarbons, which were once present in refrigerators, aerosol cans and dry-cleaning chemicals) that are capable of harming the thin, yet extremely vital ozone shield.
The state of the ozone layer was measured using weather balloons at the Syowa station (Antarctica) and other south pole stations, along with ground-based instruments and readings from satellites.
Troll, the Norwegian research station in Dronning Maud Land, Antarctica (Photo Credit: Islarsh / Wikipedia.org)
Scientists from the University of Leeds (UK), the National Center for Atmospheric Research, and MIT observed that from 2000 to 2015, the ozone hole had shrunk by 1.5 million square miles, which is a little less than one-quarter of the surface area of Russia!
Check out the official video of Science magazine about the reported healing of the ozone layer:
A healed, reinforced ozone layer will provide our planet with better protection from harmful UV rays from the Sun, as well as a number of medical ailments caused due by harmful radiation, like different types of skin cancer, especially in regions that have a thinner ozone layer.
Ozone will take a long time to recover
Although the ozone layer has shown signs of recovery, which is definitely a good thing, scientists estimate that it will not be completely healed until 2050, provided that harmful emissions and the release of ozone-threatening chemicals continue to be curbed effectively, which is a great challenge in itself. Also, the substitute chemicals (hydrofluorocarbons or HFCs) used to replace the ozone-threatening CFCs tend to contribute to global warming and climate change. In other words, it’s equally important to regulate the use of these chemicals as well. If not, it would be like treating the ozone layer at the cost of the global climate.
All in all, the mending of the ozone layer is a positive sign for life on this planet, but we need to strive continuously to lessen harmful emissions even further, and figure out environmentally friendly alternatives for the the chemicals that contribute to the hole in our ozone layer.
